Device for milling polygonal holes



P.. DEMMEL DEVICE FOR MILLING PoLYGoNAL HoLEs.

Filed De. 4, 1925 Inventor-"-- Pau] Bemmel, l 23g y Atys Patented June 7, 1927.

ATENT oFFicE. 1f

vEaux. DEMMEL, or :ammiroBiron-THE-1uArn-nonEtHEnazr,` GERMANY.

DEVICE non MrLLI'NG rotYGoNAL noLEs.

ApplicationA led December 4, 1925, Serial No.` 73,133, and in Germany January 31, 1922.

This invention relates to devices for drill-v 'ing or milling polygonal holes and has for its object to facilitate suchfoperations,

Devices for drilling polygonal holes are known which consist of two coaxial roller .milling cutters which are pressed into the material `to be milled. With such arrangements, however, it is necessary first to drill a round hole as the drilling device is not Jcapable of removing the material which has been left between the two milling cutters.

According to the present invention there` are provided auxiliary milling cutters between the two coaxial roller milling cutters .f

preferably in the form of 'two or more smaller milling -cutters with their axes parallel thereto and also rotated. These remove the material which has remained between the milling cutters so that it is possi- -ble to`produce a rectangular or' polygonal -lole without preliminary drilling. The

drive can be elected in any suitable manner, for'example-bya rope orbelt drive, by

any suitable lever or crank-transmission, by

toothed wheels, by exible-shafts, by worm gear, by compressed air,.electrically orl in any other suitable manner.

The production of holes with a larger vnumber of. corners than four isl possible by reason of the fact that the entire holding 4spindle of4 the milling cutter is always the spindle adjusting means, parts beingv shown in elevation. y Y l .I The two roller -milling cutters are indicated by 1 and 2; they are mounted on shafts 3 and 4,'which, through the mediumf of toothed gear wheels 5 and 6 are driven from a common bevel wheel 7 mounted on the shaft 9 extending upwardly in the spindle 8. Between the two millm 'cutters 1 and 2 are locatedtwo smaller ro ler milling cutters v-10 and 11r which remove the material from `:the work-piece which' has been left-between-'the two coaxial milling cutters. l

They are offs'ub'stantially the same width as the distance v bezvveen the two milling cutters 1 and 2. They are driven by the toothed gear wheels 13- and 14 from the shafts 3 and 4 of themillng cutters 1 and 2.

When the shaft'9 is rotated then, through the medium of the toothed wheel V7 and the toothedl gear wheels 5 and 6,'the two milling cutters 1 and 2 and thus, through the coy medium ofthe toothed gear wheels 13 and 14, also the roller millingY cutters 10 and 11, are rotated. The milling cutters 1 and 2 cut a rectangular hole, in the present case a square hole (see Figure 3) in the material, whilst the material which is lett in the space between the two milling cutters l and 2, is removed by .the milling cutters -10 and 11.

Adisc .member 16 is secured to'the machineand extends intov a cooperating disc receiving member 17 at the upper end spindle 8. The member 17 is secured in adjustment upon Q member 16 by a suitable clutch or equivalent means, such as a set screw 20 threaded through member `17 .and

bearing against member 16. This provides simple means for securing the spindle in adjustment about its axis. Member 17 is provided with graduations 18 which move in back of a pointer 19 secured to member 16. By releasing member 17 from member .16 the spindle, and consequently the milling cutters, can be adjusted about a vertical axis, the angle of such adjusting being in'- dicated by the gradu-ations and the pointer..v I

19. This vdevice' is used when'multi'cornered holes, for example polygonal or hex agonal holes, are to be drilled. One of the two milling cutters 1 or` 2 is removed and the work piece is drilled through by the other half of the milling cutter, whereupon the spindle 8 and thus the whole tool is ad- -justed at a suitable angle, in accordance with the dividing angle of the polygon to be produced, which can be s et by means of the graduations 18, whereupon the next sur'- faceof the polygon is cut 1n the same man'' nerA and so on.' Any well known or preferred means can be provided for locking 'discs 16 and 17 togetherafter disc 17 has been adjusted at the proper angle/.formaking the desired cut.

The drive of the various milling cutters may' naturally be effected by other means thanby toothed wheels. for example by llexible shafts or wire cables, which extend u ward'lyin the spindle 8 a`nd the like. T e latter construction is particularly suitable y'for very small milling cutters."

v tioned cutters.

3. A device for cutting polygonal holes comprising two spaced coaxial roller milling cutters, driving means passing through the space lbetween said cutters and auxiliary roller milling cutters disposed in the gap or space for cutting away material left between said firstmentione'd cutters.

4. -A device for milling polygonal holes com risin a su ortinof member two spaced coaxial roller milling cutters mou'nted upon said member and -a plurality of roller milling cutters mounted intermediate said "cutters iirst mentioned for operating in the space or ga between them.

5. A device or milling polygonal holes. comprising a supporting member, two spaced coaxial roller milling cutters mountedv upon said. member` means for. driving said milling cutters, located within said supporting member, auxiliary roller milling cutters for operating in the space `between said coaxial cutters and means 'fors driving said auxiliary cutters. f 'r 6. A device for milling polygonal holes comprising a supporting member mounted -itor angular movement, mea-ns for indicating its angular position with respect to an angularly fixed part, a roller milling cutter mounted upon said supporting member and a plurality of milling cutters also mounted upon sf' id supporting member their axes being parallel to that of the cutter first mentioned to extend t-he effective cutting surface of said cutter, means for driving said eutters said means being mounted within Said supporting member and a bearing formed in said supporting member for mounting a roller milling cutter coaxially with that irst mentioned.

7. A device for milling polygonal holes comprising a supporting member, two roller milling cutters coaxially mounted thereon in spaced relation, two smaller roller milling cut-ters mounted on said supporting member `their axes being parallel to that of the coaxial cutters and their cuttingsurfaces filling substantially l the space between said coaxial cutters, and means for driving all of said cutters.

8. A device as claimed in claim 7 whenein the driving means is located within the supporting member.

9. A device as claimed in claim 7 wherein the driving means comprises a rotating shaft and lbevel and spur gearing.

g 10. In a device for milling polygonal holes, a drive shaft, a spindle adjustable about the shaft, a pair of main roller milling cutters coaxially mounted at the lower end of the spindle, supplemental roller milling cutter mounted between the two main cutters, all of said cutters being disposed parallel, and driving connections between the cutters and said shaft. l

In testimony whereof I' aiiix my signature.

PAUL DEMMEL. 

